過去研究指出，公司管理當局可藉由即時揭露更多攸關資訊以降低市場之資訊不對稱，而管理當局所發布之財務預測亦為揭露資訊之一種。我國證管會於民國八十年五月起正式實施強制性財務預測制度，影響資本市場甚鉅。本研究旨在探討管理當局所發布之財務預測對資本市場資訊不對稱之影響，進而推論我國強制性財務預測制度對於降低資本市場之資訊不對稱是否有其功效。 本研究採用股票交易量、股價變異性及市場深度作為資訊不對稱之代理變數，實證結果顯示： 1.在強制性財務預測制度實施前，自願發布財務預測之公司於預測發布後，其資訊不對稱顯著較預測發布前降低；然與未發布財務預測公司相較之結果卻顯示，以股票交易量為資訊不對稱之代理變數時，發布財測公司於預測發布後之資訊不對稱反而顯著較未發布財測者為高。 2.在強制性財務預測制度實施後，強制或自願發布財務預測之公司於預測發布後，其資訊不對稱程度仍顯著較其發布前降低；而以股價變異性為資訊不對稱代理變數之結果亦顯示，發布財測公司於預測發布後之資訊不對稱顯著較未發布公司為低。 3.以市場深度為資訊不對稱代理變數之結果顯示，在強制性財務預測制度實施後，發布強制性財務預測之公司，其資訊不對稱於預測發布後顯著降低；此外，與發布自願性財務預測公司相較之結果顯示，發布強制性財測公司於預測發布後，其資訊不對稱程度不顯著高於發布自願性財務預測者。 / A firm can increase levels of disclosure to lower the information asymmetry. Financial forecast released by managers is also one of information about corporation. Our country began to implement the mandatory financial forecast regulations since May, 1991. This study mainly investigates the association between financial forecast released by companies and the mandatory financial forecast regulations. Furthermore , it also investigates that if the regulations effectively mitigate information asymmetry. This study uses trading volume, price volatility, and market depth as proxies for the information asymmetry. The empirical results show that: 1.Before May, 1991, corporations with voluntary forecast significantly mitigated the information asymmetry after the forecast released. But the information asymmetry (use trading volume as a proxy) of corporations after forecast released was not significantly lower than corporations without forecast. 2.After May, 1991, corporations with mandatory or voluntary forecast also significantly mitigated the information asymmetry after the forecast released. And the information asymmetry (use price volatility as a proxy) of corporations after forecast released was significantly lower than corporations without forecast. 3.After May, 1991, corporations with mandatory forecast significantly mitigated the information asymmetry (use market depth as a proxy) after the forecast released. And the information asymmetry of corporations after mandatory forecast released was not significantly higher than corporations with voluntary forecast.